I think his only mediocre Smash is DSmash cause its angle and knockback insofar as the front hit (which is where you'll usually hit with it) aren't that impressive.
Relative to his moveset, Luigi's Down Smash isn't "good". Relative to the cast, it's probably one of the better ones for pure damage, get off me, and low risk. It's frame 6-7 or 14-15, 4 total active frames, takes 29 frames to recover, and only has 37 total frames. Both hits do 14% or 15% and while the front hit doesn't send people at a great angle, the sheer speed, safety, and damage his Down Smash does is just stupid. You'd know who love to have this Down Smash? Mario, Sheik, maybe even Dr. Mario, Marth, Lucina, Roy, Ike, and a bunch more. (Dr.) Mario would love having 37 total frames instead of 43 and do more damage at the cost of having separate hitboxes, 1 more frame of startup, and
Along with Up Smash which, come on, (Dr.) Mario, Luigi, Rosalina, Wario, Peach, and Bowser, so everyone, but Bowser Jr., have partial invincibility. Bowser's is slow, Peach doesn't really cover much area, and Wario's recovers longer, but the rest? (Dr.) Mario, Luigi, and Rosalina? They should be spamming the hell out of that anti-air. Mario and Rosalina players, especially Ally and his Mario, abuse the hell out of Up Smash and Dr. Mario players have been starting to. What about Luigi players, though? There's almost no risk. As of right now, it has the same hit frames and total frames as Dr. Mario meaning it has an extra frame to Mario's Up Smash. Luigi's does 1.68% or 3.68% less, but it's almost the same move and equally as safe. So why not?
Even if D-throw overshadowed a lot of pre-patch Luigi's options as D-throw and Uair did for pre-patch Diddy, with the frame data for his Up and Down Smashes and the fact his Up Smash can be used in the same way as Mario, everyone should have expected Luigi players to abuse the hell out of these moves. Well, with how his D-throw can setup Up and Down Smash, we might be seeing more of them.
Late reply:
Ally lost to Poke in the Luigi ditto back at EXP. He also tried going ROB in the MU (or was that against V115's ZSS?). But yeah, he eventually goes back to playing Mario.
He said (well, more like ranted) similar thoughts about Luigi's reward of a grab being too silly and braindead, along with rants on ZSS. I do remember that Ontario's players commented saying things about Mario going even with Luigi, and V115 thinks that Mario beats ZSS.
I remember that, but I forgot about him using ROB... So, Ally's used at a decent to high level, Captain Falcon, Falco, Luigi, Marth, Meta Knight, ROB, and I believe, Shulk. I would count Lucina, but that was more of a "let's have fun since I'm not going to win against ZeRo." Adding Mario to the mix, Ally's got 7 characters under his belt.
ZSS is at least held back by a very punishable grab. It's high risk and high reward for her unlike Luigi where even if it could be considered high risk, the reward was beyond massive relative to any character even including ZSS, DK, and pre-patch Diddy. Now, Luigi's more like, low risk and medium reward which is fine. That's kind of the same as Sheik, Mario, the Pits?, Diddy, and more.
As for ZSS and V115, I don't know how well V115 plays. Well, I think he is a good player, but I think he makes really silly mistakes at times. I remember a match were he fought BlackTwins's Falco. BlackTwins isn't a Falco player; he's a Mario player. I think V115 SD'd like twice the entire set of Losers Finals and basically gave BlackTwins a victory. MU inexperience or not, SD'ing like that isn't indicative of the players skill if they royally screwed up two times and couldn't make up the massive disadvantage. I don't know enough to say anything about the Mario and ZSS MU, so what's said here is totally holds nothing, but I don't think Mario beats her. Even ignoring that Nairo might be a level above Ally in player skill, the fact that ZSS's advantage is extreme, but checked by a very punishable whiffed grab and that Mario doesn't exactly kill as easily as ZSS and his advantage kind of pales in comparison to her, I can't see how Mario would hold an advantage not matter how slight against ZSS. If anything, V115 might be held back by himself than anything and that at worse, ZSS is even with Mario, but V115's mistakes are making it much worse.
Does Link's second jab have IASA frames or something?
All moves have "IASA" or "FAF"; uselessly padded terms total frames can take care of. The main thing is that some moves, particularly controlled multi-hits like many jab combos, Link's Side Smash, Marth's Dancing Blade, or Shulk's Air Slash, have transition frames which occur earlier than total frames so you can actually hit with those moves and not be screwed, like, if Fox had no transition frames for his jab, it would effectively be the worst jab by a huge margin. Even with its low total frames of 17 for jab 1, it'd be completely useless for trying to do a complete jab combo or a jab mixup unless at higher percents because of jab 1's low knockback and lack of jab 2 to safely confirm a jab mixup.
Short answer: Link's jab has and always will have "IASA" or total frames, but they increased his total frames for jab 1 and jab 2. Link's jab 1 or jab 2 used to have the same total frames as Samus's, 17, but does more base knockback and was disjointed making it much safer than Samus's jab.